Biomolecule

• Biomolecule


  A chemical compound found in living organisms, composed mainly of carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus. Biomolecules are the building blocks of life and perform important functions in living organisms.
• Major categories of biomolecules

  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids
• Describe carbohydrates and its classification

  1. Monosaccharides

  2. Disaccharides

  3. Polysaccharides

  
• Monosaccharide


  The most basic form of carbohydrates, the simplest sugar and basic sub-unit of a carbohydrate

  
• Examples of monosaccharides

  • Fructose
  • Glucose
  • Galactose

  
• Disaccharide


  A substance composed of two molecules of simple sugars (monosaccharides) linked to each other
• Examples of disaccharides

  • Sucrose (glucose + fructose)
  • Lactose (galactose + glucose)
  • Maltose (glucose + glucose)

  
• Polysaccharide


  Large molecules made up of many smaller units (monosaccharides) joined together
• Examples of polysaccharides

  • Starch
  • Glycogen
  • Cellulose

  
• Protein


  A highly complex substance present in all living organisms, consisting of amino acid residues joined by peptide bonds
• Proteins are made up of carbon, hydrogen, oxygen, nitrogen and sulfur
• Lipid


  A heterogeneous group of compounds including fats, oils, steroids, waxes and related compounds, that are relatively insoluble in water and soluble in non-polar solvents
• Lipids are made up of carbon, hydrogen and oxygen
• Functions of lipids

  • Storage form of energy
  • Important dietary components
  • Structural components of biomembranes
  • Thermal insulators
• Classifications of lipids

  • Simple lipids
  • Complex lipids
• Simple lipids


  Esters of fatty acids with various alcohols, including fats (esters of fatty acids with glycerol) and waxes (esters of fatty acids with higher molecular weight monohydric alcohols)
• Complex lipids


  Esters of fatty acids containing groups in addition to an alcohol and a fatty acid
• Nucleic acid


  There are two kinds: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA contains the genetic information that codes for protein sequences, while RNA carries out protein synthesis.
• DNA


  • A double-helix consisting of two linear strands of polymerized nucleotides bound together by hydrogen bonds between paired nucleotides (A-T, C-G)
• The monomers of nucleic acids are nucleotides, which are compounds consisting of a nucleoside linked to a phosphate group
• Nucleotides form the basic structural unit of nucleic acids such as DNA
• Chemical tests to identify biomolecules

  • Iodine test for starch
  • Biuret test for protein
  • Benedict's test for reducing sugars
  • Ethanol emulsion test for lipids
  • Diphenylamine test for nucleic acids

  
• The presence of nucleic acids can be tested using the Diphenylamine test, where DNA turns the solution blue and RNA turns it green
• Structures of biomolecules

  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids

  
• Food labels provide nutrition information to help consumers make smart choices, including serving size, calories, nutrients, and percent daily values